Improved performance of lateral flow immunoassays for alpha-fetoprotein and vanillin by using silica shell-stabilized gold nanoparticles.
Mikrochim Acta
; 186(1): 2, 2018 12 04.
Article
en En
| MEDLINE
| ID: mdl-30515570
ABSTRACT
The sensitivity of lateral flow assays (LFA) was increased 30-fold by making use of spherical core-shell gold-silica nanoparticles (AuNP@SiO2 NPs). They can be prepared by silylation of surfactant stabilized AuNPs. The AuNP@SiO2 NPs are highly stable and can be used to label antibodies at virtually any concentration. The detection limit of an LFA for alpha-fetoprotein (AFP) can be decreased from 10 ng·mL-1 to 300 pg·mL-1 which makes it comparable to an enzyme-linked immunosorbent assay. To demonstrate the applicability to an immunoassay, a sandwich assay was developed for vanillin by covalent modification of the AuNP@SiO2 NPs with antibody. By using the method, vanillin can be detected visually in milk powder samples in concentrations as low as 100 ng·g-1. With unique optical property and great stability, this AuNP@SiO2 endows great potential in biosensing applications. Graphical abstract Controlled growth of AuNP@SiO2. The newly prepared AuNP has a negative hydration layer. This layer is further surrounded by a bilayer of CTAB through electrostatic attraction. The hydrophobic inner layer enables the access and assembling of APTES and MTTS. After the hydrolysis of siloxane, a thin layer of silica shell is formed around AuNP.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Benzaldehídos
/
Alfa-Fetoproteínas
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Dióxido de Silicio
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Nanopartículas del Metal
/
Oro
Límite:
Animals
Idioma:
En
Revista:
Mikrochim Acta
Año:
2018
Tipo del documento:
Article
País de afiliación:
China